#include<bits/stdc++.h>
#define pi 3.14
using namespace std;

int main()
{
    int h,r;
    cin >> h >> r;
    double v = (h/10.0)*(3.14*(r/10.0)*(r/10.0));
    int n = (int)((20.0/v)+1);
    cout << n << endl;
    return 0;
}